A novel conductive membrane sensor protection technique to mitigate redox-active interferences

Abstract

Due to their high specificity and selectivity, receptor-based biosensors play an important role in real-time health monitoring. However, maintaining an ideal homeostatic sensor environment while correcting for the physiological variability of biofluids is imperative. Biological media contain an abundance of interfering species which if not addressed, can render the biosensor inoperable. Enzyme-based electrochemical sensors are particularly susceptible to redox-active interferences as these increase analyte detection limits, making physiological measurements a challenge. For this reason, extensive research has been applied to develop various strategies to mitigate such interferences. Here we present a novel conductive membrane encapsulation strategy designed to mitigate redox-active interferences while allowing redox-inactive target analyte to pass through unaltered to the sensor surface. This redox-active mitigation strategy is highly generalizable as the potential across the conductive membrane can be easily modified. Using a first-generation glucose oxidase sensor as a model interferent-sensitive system, we have shown a 72 percent reduction in redox-active interference and an 8-fold decrease in detection limit upon implementation of our conductive membrane strategy.

Keywords

• Biosensors
• Membranes
• Conductive
• Redox-active interferents
• Electrochemical glucose biosensors